Air distribution terminal



1969 M. H. COLEMAN ET AL. 3,422,888

AIR DISTRIBUTION TERMINAL Filed June 29, 1967 FIG. 2

INVENTORS. MILTON H. COLEMAN. DARWIN. G. TRAVER.

' ATTORNEY.

United States Patent M 8 Claims ABSTRACT OF THE DISCLOSURE A roomterminal for use in an air conditioning system employing reheat coils inthe terminal to compensate for varying loads in the area served thereby.The unit is provided with a nozzle sheet for discharging the temperedair through a stack for inducing room air therethrough for furthertempering the conditioned air.

Background of the invention This invention relates to air conditioningunits. More particularly, this invention relates to air conditioningunits of the reheat type wherein air is conditioned at a central stationand distributed to a plurality of air conditioning units for dischargeinto the area served by the units. A heat exchanger supplied with aconditioning medium is provided in each unit to temper the air flowingtherethrough. By controlling the flow of conditioning medium accordingto the cooling load on the area being conditioned, the temperature ofthe area can be closely maintained at the desired level. For peak systemefficiency, it is desirable to supply a minimal volume of conditionedair to the area being conditioned. To maximize unit efficiency whileminimizing conditioned air volume, the conditioned air must be suppliedat low temperatures. However, if extremely low temperature air were tobe discharged into the conditioned area, problems would be encounteredin attempting to mix the discharged air with room air sufficiently toprevent cold drafts in the area from causing discomfort to the occupantsthereof.

Summary of the invention In accordance with the preferred embodiment ofthis invention, an air conditioning terminal is provided for receivingconditioned air from a central source and discharging it through abalancing damper, tempering coils, and then through novel dischargenozzles arranged for inducing room air into a stack portion of the unitto cause mixing of the conditioned air and room air so that the airdischarged from the unit is warmed sufficiently to minimize cold draftsin the area being conditioned.

Brief description of the drawing FIGURE 1 is a sectional end view of avertical reheat type room terminal; and

FIGURE 2 is a partial perspective view of the nozzle plate of ourinvention.

Description of the preferred embodiment Referring to the drawings, thereis illustrated a room terminal forming part of an air conditioningsystem of the kind used in large ofiice buildings. The unit is generallyknown as a blow-through reheat unit and includes a casing comprising afront panel 5 provided with a room air inlet grille 7 and a top panel 9having a mixed air outlet grille 11 therein. Within the casing there isprovided a first enclosure 13, divided into a top plenum 15 and bottomplenum 17 by a sliding plate balancing damper 19. An inlet 18 isprovided in the enclosure 13 to provide conditioned air from a centralsource (not shown) to bottom plenum 17. A second enclosure or temperingchamber 21, in communication with top plenum 15 is provided 3,422,888Patented Jan. 21, 1969 with a tempering coil 23 for passage of a heatexchange medium such as hot water therethorugh. The first and secondenclosures are lined with sound attenuating material 20 such as glassfiber blanket which also acts as insulation to minimize condensation onthe enclosures. A triangularly shaped sound absorbing bafile 25 such asdisclosed in application Ser. No. 649,942 filed concurrently with thisapplication is disposed in top plenum 15 between damper 19 and chamber21.

Discharge nozzle sheet 27 having a plurality of double nozzle rows 29directs the tempered, conditioned air through mixing stack 31, therebyinducing room air to flow through opening 33 in stack 31 and mix withtempered air before being discharged into the room through dischargegrille 11. Referring more particularly to the nozzle sheet, it can beseen that the nozzle pairs are comprised of relatively flat triangularshaped opposed upstanding walls 35 and 37 joined to the nozzle sheet byradius 38. The sides 35 and 37 are connected at their ends by generallycurved upstanding end sections 39 and 41. A central V-shaped portionhaving curved walls 43 and 45 forms a partition to provide two nozzlesfrom each pair of upstanding walls. This central partition results intwo air streams from each nozzle, thereby increasing the inductioninterface between primary air and room air to improve mixingtherebetween. The nozzle sheet has a curved lip 47 formed about itsperiphery to collect condensation that might form on the outside ofstack 31 and on discharge nozzle sheet 27 due to the temperaturevariation between the cold air flowing through the unit and the warmroom air. A space 51 is provided between the four sides of stack 31 anddownwardly extending portions 53 of discharge grille 11. The dischargeof air from stack 31 induces a flow of warm room air through space 51thereby providing a warm blanket of air along downwardly extendingportions 53 to insulate the top panel 9 from the cool air dischargedfrom the unit to prevent condensation from forming thereon.

The smooth contours of the nozzle sheet and the stack result in a unitespecially suitable for use in hopsital installations due to the easewith which the external surface of the nozzle sheet and the stacksurfaces may be sanitized. The design of the'nozzles also results inefficient mixing of the conditioned and room air to prevent drafts inthe area being conditioned.

While we have described a preferred embodiment of the invention, it isto be understood the invention is not limited thereto but may beotherwise embodied within the scope of the following claims.

We claim:

1. A room terminal for use in an air conditioning system comprising:

a first enclosure adapted for connection to a source of conditioned air;

a second enclosure communicating with said first enclosure;

heat exchange means disposed in said second enclosure for tempering theconditioned air passing therethrough from said first enclosure;

nozzle means associated with said second enclosure for discharging thetempered air therefrom; and

a mixing stack associated with said nozzle means for passage of airdischarged from said nozzle means, said stack being oriented so as toprevent impingement of discharge air thereon, said stack having anopening therein along a surface defined by the edge of the air streamsdischarged from said nozzle means so as to cause room air to be inducedinto said stack by the air streams for mixing room air and conditionedair to further temper the conditioned air before it is discharged intothe room.

2. A room terminal according to claim 1 further including:

a casing having a top panel and a front panel associated therewith, saidtop panel being adapted for discharge of air into the room;

a room air inlet grille disposed in the front panel of said casing foradmission of air into said casing for induction through said stack;

means associated with said top panel and said stack for inducing roomair therebetween to produce a blanket of room air to insulate the toppanel of said casing from the air discharged from said stack.

3. A room terminal according to claim 2 wherein said means includes adischarge grille disposed in said top panel, said grille havingdownwardly extending grille portions overlying the top edge of saidstack so as to provide a spacebetween said stack and said portions forinduction of air therebetween.

4. A room terminal according to claim 1 further including a slidingplate damper dividing said first enclosure into a top plenum incommunication with said second enclosure and a bottom plenum adapted forconnection to a source of conditioned air, said damper being adjustableto regulate the quantity of air flowing through the unit.

5. A room terminal according to claim 1 wherein said nozzle meanscomprises a generally rectangular flat nozzle sheet having an up-turnedflange along the periphery thereof, said nozzle sheet having a pluralityof parallel paired nozzles formed therein, each of said nozzle pairshaving generally triangularly shaped opposed upstanding walls formed onsaid nozzle sheet for discharge of air therebetween, said upstandingwalls being joined to each other at the ends thereof by generally curvedupstanding end sections, each of said nozzle pairs having a generallyU-shaped partition between the upstanding Walls thereof midway betweenthe ends to form the two nozzles comprising the nozzle pair, the nozzleorifices lying in a plane disposed at an angle to the plane of thenozzle sheet, the axis of said mixing stack being disposed perpendicularto the plane containing the nozzle orifices.

6. Air discharge means for use in an air conditioning room terminalcomprising:

a nozzle sheet;

said nozzle sheet including a generally flat panel having a plurality ofparallel nozzles formed therein, each of said nozzles having opposedupstanding walls formed on said nozzle sheet for discharge of airtherebetween, said upstanding walls being joined to each other at theends thereof by generally curved upstanding end sections.

7. Air discharge means according to claim 6 wherein said parallelnozzles have a generally U-shaped partition between the upstanding wallsmidway between the ends thereof to form two nozzles from each pair ofopposed upstanding walls.

8. Air discharge means according to claim 6 wherein said opposedupstanding walls have a generally triangular shape, the nozzle orificesthereby lying in a plane disposed at an angle to the plane of the nozzlesheet.

References Cited UNITED STATES PATENTS 2,855,840 10/1958 Simmons 98383,012,760 12/1961 McGrath 165l46 3,327,605 6/1967 Shourmaker 9838 ROBERTA. OLEARY, Primary Examiner.

T. W. STREULE, Assistant Examiner.

US. Cl. X.R.

